The body uses nutrients in cooperation with each other. You cannot say there is one nutrient more important than all the others. In fact, the lie of the nutrition industry is that you can separate out a vitamin from other vitamins (like vitamin C) and shock-load your body with that particular vitamin and get a better nutritional result. In reality, your body requires a number of other nutrients to digest and properly utilize that vitamin C. If you do not get your nutrition holistically, like when you eat a tomato or a carrot, and instead take it in a pill form, you force your body to leach valuable nutrients from other parts of your body just to properly use the vitamin you shock-loaded your body with. Otherwise, your body simply excretes it as waste and you have accomplished nothing.